Determination of friction characteristics of J-55 OCTG connections lubricated with environmentally safe thread compound

This paper presents the results of an experimental study conducted to deter mine friction coefficient of J-55 tubing with eight different compounds. Fo ur of the compounds meet the specifications of API Modified, and four were lead-free. The specimens were machined and phosphatized with manganese phos phate. The surface roughness of the specimens was nominally 1.27,micron. Re peated tests, were run at a rotational speed of 1.5 rpm and 5 rpm. In each test the bearing load was increased monotonically to a maximum of 625 kN. F riction coefficient data obtained during the tests are presented and discus sed.